In recent years, as an example of augmented reality (AR) technology, display by superimposing computer graphics (hereinafter, referred to as CG) on an image of a real space captured by a camera has become common. That is, an object drawn by CG (hereinafter, referred to as a virtual object) is disposed within a virtual space associated with the position of the real space, and thus is displayed by superimposition on the image of the real space in a form matching the viewpoint of a user. Thereby, the user can feel as if the virtual object is present in the real space. Hereinafter, the virtual space in which the virtual object is disposed in association with the position of the real space is referred to as an “augmented real space.”
In augmented reality technology, a technique in which a plurality of users share an augmented real space is disclosed in, for example, Patent Literature (hereinafter, abbreviated as “PTL”) 1. PTL 1 discloses a technique for sharing position information of a reference point serving as a reference when the augmented real space is constructed, among a plurality of users (hereinafter, referred to as a sharing procedure). In the technique of PTL 1, it is possible to form a group of users sharing the augmented real space which is constructed on the basis of a predetermined reference point.
The technique disclosed in PTL 1 assumes a situation where a plurality of groups formed gather together and all the users belonging to each group share the augmented real space. For example, the technique assumes that a plurality of users belonging to family A share virtual pet A in augmented real space A and also that a plurality of users belonging to family B share virtual pet B in augmented real space B. In this case, the technique may be used to allow all the users belonging to family A and family B to share virtual pet A and virtual pet B.